// Copyright(c) 2019 - 2020, #Momo
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// modification, are permitted provided that the following conditions are met :
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// 1. Redistributions of source code must retain the above copyright notice, this
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// 2. Redistributions in binary form must reproduce the above copyright notice,
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#pragma once

#include "Platform/GraphicAPI.h"
#include "Utilities/ECS/Component.h"
#include "LightBase.h"

namespace MxEngine
{
    class DirectionalLight : public LightBase
    {
        MAKE_COMPONENT(DirectionalLight);
    
    public:
        constexpr static size_t TextureCount = 3;

    private:
        std::array<Matrix4x4, TextureCount> matrices;

        Matrix4x4 ComputeCascadeMatrix(size_t cascadeIndex, float aspectRatio, float fov, const Matrix4x4& viewMatrix) const;
    public:
        bool IsFollowingViewport = false;
        TextureHandle DepthMap;
        Vector3 Direction = MakeVector3(0.0f, 1.0f, 0.0f);
        std::array<float, TextureCount> Projections = { 5.0f, 25.0f, 250.0f };
        float DepthScale = 20.0f;

        DirectionalLight();

        void OnUpdate(float dt);
        const Matrix4x4& GetMatrix(size_t index) const;
    };
}